Dematin

Dematin (Band 4.9)

Originally isolated from the erythrocyte skeleton, dematin is a tetra-meric actin filament bundling protein. The actin binding domain at the C-terminus is homologous to the villin "head piece" a region (Rana et al, 1993) found at the C-terminus of villin a second actin-binding domain exists close to the N-terminal . Dematin is present as two forms a small and a large form the difference is accounted for by an insertion in the C-terminus that contains a P-loop found in band 4.2. Dematin is a substrate for PKC and PKA and bundling of actin (Siegel & Branton, 1985) is regulated by phosphorylation (Husain-Chishti et al, 1988) by PKA but not PKC.

References:-

Azim, A. C., J. H. M. Knoll, et al. (1995). "Isoform cloning, actin binding, and chromosomal localization of human erythroid dematin, a member of the villin superfamily." J.Biol.Chem. 270(29), 17407-17413.

Azim, A. C., S. M. Marfatia, et al. (1996). "Human erythrocyte dematin and protein 4.2 (Pallidin) are ATP binding proteins." Biochemistry 35, 3001-3006.

Husain-Chishti, (1988). Nature 334, 718-721.

Husain-Chishti, A., Faquin, W., Wu, C.-C. & Brandon, D. (1989). J.Biol.Chem. 264, 8985-8991.

Siegel, D. L. & Branton, D. (1985) Partial purification and characterization of an actin-bundling protein, Band 4.9, from human erythrocyte, J.Cell Biol. 100, 775-785.

Roof, D. J., Hayes, A., Adamian, M., Chishti, A. H. & Li, T. (1997) Molecular characterization of abLIM, a novel actin-binding and double zinc finger protein, J.Cell Biol. 138, 575-588.

Rana, A. P., Ruff, P., Maalouf, G. L., Speicher, D. W. & Chishti, A. H. (1993) Cloning of human erythroid dematin reveals a novel member of the villin family, Proc. Natl. Acad. Sci. 90, 6651-6655.